A series of wars, known collectively as the Napoleonic Wars, extended French influence to much of Western Europe and into Poland. At its height in 1812, the French Empire had 130 departments, ruled over 70 million subjects, maintained an extensive military presence in Germany, Italy, Spain, and the Duchy of Warsaw, and counted Prussia and Austria as nominal allies.[8] Early French victories exported many ideological features of the French Revolution throughout Europe: the introduction of the Napoleonic Code throughout the continent increased legal equality, established jury systems and legalised divorce, and seigneurial dues and seigneurial justice were abolished, as were aristocratic privileges in all places except Poland.[9]

The Battle of Marengo (14 June 1800) inaugurated the political idea that was to continue its development until Napoleon's Moscow campaign. Napoleon planned only to keep the Duchy of Milan for France, setting aside Austria, and was thought[by whom?] to prepare a new campaign in the East. The Peace of Amiens, which cost him control of Egypt, was a temporary truce. He gradually extended his authority in Italy by annexing the Piedmont and by acquiring Genoa, Parma, Tuscany and Naples, and added this Italian territory to his Cisalpine Republic. Then he laid siege to the Roman state and initiated the Concordat of 1801 to control the material claims of the pope. When he recognised his error of raising the authority of the pope from that of a figurehead, Napoleon produced the Articles Organiques (1802) with the goal of becoming the legal protector of the papacy, like Charlemagne. To conceal his plans before their actual execution, he aroused French colonial aspirations against Britain and the memory of the 1763 Treaty of Paris, exacerbating British envy of France, whose borders now extended to the Rhine and beyond, to Hanover, Hamburg and Cuxhaven. Napoleon would have ruling elites from a fusion of the new bourgeoisie and the old aristocracy.[10]

On 12 May 1802, the French Tribunat voted unanimously, with the exception of Carnot, in favour of the Life Consulship for the leader of France.[11][12] This action was confirmed by the Corps Législatif. A general plebiscite followed thereafter resulting in 3,653,600 votes aye and 8,272 votes nay.[13] On 2 August 1802 (14 Thermidor, An X), Napoleon Bonaparte was proclaimed Consul for life.

Pro-revolutionary sentiment swept through Germany aided by the "Recess of 1803", which brought Bavaria, Württemberg and Baden to France's side. William Pitt the Younger, back in power over Britain, appealed once more for an Anglo-Austro-Russian coalition against Napoleon to stop the ideals of revolutionary France from spreading.